I use the following rewrite rule to remove the .php extension from my page urls:
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^\.]+)$ $1.php [NC,L]
This works great in the root directory of my website as well as in the admin subdirectory with the exception of /admin/index.php
If I try to go to /admin or /admin/ without specifying the filename I get this error:
The requested URL /admin/.php was not found on this server.
Any ideas on how to resolve this?